Cadillac STS Forum - 2005 through 2012 Discussion, Low/High/Fog Lamps On Simultaneously. in Past Cadillac Vehicle Discussion; I understand this is not supposed to occur and I believe it violates FMVSS/CMVSS. Does anyone's car do this?...

Re: Low/High/Fog Lamps On Simultaneously.

Originally Posted by ddalder

Yup, that is the way it is supposed to work. I'm not sure why I can turn all mine on together.

Darcy...I think, it has something to do with your rear fog mod....you changed something in your cars programming/setup by "activating" the rear fog function via Tech II...cause this is an export-only option...

(side note: ...in the past I once changed the german export setup to the canadian setup on my 97 Seville STS by playing with the "deeper" DIC programming...et voilā...no rear fog function anymore...and so the front fogs...they also didn't work with high beam anymore ...)

Yeah my money is on the export fog option you enabled.
Mine behaves like yours (all on together) only because I added a jumper in the relay center to activate the fog relay with the parking light relay. This also turns on the fogs during remote start.

I would however rather have the computer keep them on during high beams instead.

As you selected here, it doesn't say rear fogs, its non-us/can fogs. So I would assume that the 4 light limit is only present in USA/CAN.

Yeah my money is on the export fog option you enabled.
Mine behaves like yours (all on together) only because I added a jumper in the relay center to activate the fog relay with the parking light relay. This also turns on the fogs during remote start.

I would however rather have the computer keep them on during high beams instead.

Re: Low/High/Fog Lamps On Simultaneously.

They are both to Pin 86 on the relay.
This should be the trigger to enable the relay, and the fogs will still get their power via the Fog relay.
Your relays could be installed with the 2753 facing the other direction, for this to work I believe they need to be installed the way mine are pictured.
I used what looks like about a 18 or 20 gauge solid wire (not stranded) - there is very little current that flows here, if I remember correctly all this is doing is 'grounding' the relay which is what is used to turn the relay on and off.
I've gone 20,000 miles with the car in this configuration with about 15,000 of those miles being night time driving while I worked overnights.
I just did a single loop around pin 86 on each of them taking care that they don't contact anything else.

I had done a similar setup on my 02 Deville, but in that case I linked 3 relays together with some diodes to keep lowbeams on with Highs and Fogs on with Highs; in that case I used pin 86 from those three relays with diodes in place to prevent the highs and lows from turning on when I only turned on the fogs.

Note: Any time your parking lights (not DRL) are on the fogs will be on.
You will _not_ see the fogs on indicator lit up on the dashboard unless you manually turn them on.
You can still toggle the fogs on and off when your low beam headlights are off and your parking lights will go on and off accordingly.
Your Highbeams will be able to turn on and off without affecting the fogs being on or off.

*With this override you will not be able to turn off your fog lamps when your headlights are on.*

Re: Low/High/Fog Lamps On Simultaneously.

It is nice that I basically have full control. The only thing I've noticed is that I can't turn on my rear fog lights without turning on the front fogs first during daylight hours. At night they will operate independently.

Re: Low/High/Fog Lamps On Simultaneously.

I'd suggest using discretion when using your lights and approaching other cars at night. While in Norfolk this Summer, we got visually blasted and partially disoriented by an overtaking AWD pickup on our way back to the hotel after a midnight cruise.

I like to see where I'm going as much as the next guy, but I wasn't in the fast lane and this bozo with a dozen glaring lights, pulled up right behind me, causing odd reflections and a bunch of unexpected shadows. Thankfully, he soon passed. Do as you will but consider other drivers, too.

Re: Low/High/Fog Lamps On Simultaneously.

Agreed. I try to be very considerate and respectful of other drivers. In fact, I generally don't use my IntelliBeam in the city because I don't feel it responds quickly enough. The only time I can anticipate ever using low, high and fog lights together is in the country on back roads or rural highways where there is little or no traffic. I find some of the headlights people are self-installing very irritating. Many of these are poorly aimed, produce far too much glare, or a little of both. Some oncoming traffic is very hard on the eyes.

Re: Low/High/Fog Lamps On Simultaneously.

The only thing I've noticed is that I can't turn on my rear fog lights without turning on the front fogs first during daylight hours. At night they will operate independently.

...maybe a stupid question and comment...but were your head- and taillamps "on" during daylight hours, when you tried to turn on the rear fogs first (before front fogs) during daytime?
...I ask, because the rear fog lamps only should work with at least the parking lamps/lighting on...they are not allowed to work alone, without any other lighting on...(and the amber drl doesn't count, n/a on export )

My rear fogs will only work independently, when:

Lighting/"driving lights" (head- and tail) are on (e.g. manually switched on at daytime (switch position "headlamps") or on with AUTO-mode (switch position "AUTO") automatic on in the later hours/in the night)

When the lights are off (e.g. during daylight) the rear fogs won't work...they don't come on when I try to/using the switch(position)...I first have to turn on the front fogs (which also activates the little parking lamps, taillamps, license plate lamps and the amber and red sidemarker)...
...same with the parking lamp mode (switch position "parking lamp")...I have to turn on the front fogs first, before I can switch on the rear fogs...

(btw...little offtopic side note...IntelliBeam also wasn't available on euro and most other exports)